What is Application Modernization?

Application modernization is a big topic. There are several useful approaches and strategies that can be implemented individually or in tandem to achieve a modernized application. There are also pitfalls and gotchas that can slow down the process, increase cost, and worse. We’ll review the most common types of application modernization and how to apply the right approach and right implementation for your specific needs.

Definition: What is application modernization?

In simple terms, application modernization is the process of updating older, legacy software to utilize modern technology, architectures, computing methods, or practices. These updates can include using new languages, frameworks, integrations, and infrastructure. 

An illustrative example of this is performing extensive upgrades and repairs to an older car. Even though an older car may still perform its essential functions, it is important to address problems or concerns before they become bigger problems. Your goal is to continue using the car but maintenance and repair has become difficult, expensive, and time consuming. Adding better tires, upgrading the suspension, and replacing broken parts with newer, modern parts will help the car function better, last longer, and be easier to maintain. Modernizing your application follows this same pattern – fixing, improving, and upgrading will lead to easier maintenance, lower cost, and better user experience. And just as finding old car parts that are no longer being produced leads to expensive, frustrating car maintenance and repair, finding and hiring qualified team members who know the required legacy coding languages will only get more difficult. In many of the same ways as this car example, an application can be modernized to improve its function and extend its lifespan by implementing modern technology using updated software practices. 

Common examples and reasons for modernization:

  • LAMP stacks (Linux, Apache, MySQL, PHP) – while these stacks may have some life left in them it is common to modernize by moving to cloud infrastructure, restructuring the architecture, improving the data layer (e.g., migrating to a new database), or rewriting code using a modern framework and language.
  • Monolith applications – your imagination may go directly to old banking systems running COBOL on a mainframe, but monoliths come in all shapes and sizes. Even newer applications built on anything from .NET to Java can have a monolith architecture and be a good target for modernization.
  • User expectations and business demands – if an application cannot keep up with user demands for new functionality and business requirements to integrate with other apps, it quite literally must be modernized. Customer-centric innovation is no longer an optional luxury. Moving from manual deployments to CI/CD automation, monoliths to microservices, black box data tiers to open APIs, are all ways modernization can enable an application to be more nimble, empower customer-centric innovation, and meet ever-changing requirements and expectations.

Why modernizing is essential

Legacy applications have unique and challenging support requirements, and although legacy applications are mostly defined by their age they can also be defined by their relationship to the business. One way to think of this is that businesses and technology have a symbiotic relationship, and an application becomes legacy when that symbiosis turns parasitic. The legacy application then begins to demand specialized knowledge (the app won’t start until all twelve background services are running), requires extra sensitivity to business needs (never reboot the servers on the second Wednesday because the overnight job runs long processing month-end reports), and becomes difficult to update (our next maintenance window isn’t for 7 weeks). This parasitic relationship creates additional tech debt along with a sense of busy-ness felt by entire teams simply to keep the application in a steady state. This tech debt and busy-ness is real and it has an impact. A 2018 Deloitte survey found that the average enterprise spends 57 percent of its IT budget on supporting legacy operations and only 16 percent on innovation. Modernization is essential to counteract the inertia of tech debt and the busy-ness that it requires.

Continuing to run a legacy application may be a requirement from the business, but it comes with risks and consequences that materialize sooner or later. These can show up in the form of losing vendor support, paying excessive licensing costs, struggling with new security standards and the risks that come with noncompliance, failing to deliver new features and functionality demanded by users, struggling to hire talent, or over-provisioning hardware to scale vertically because that is the only option.

Modernizing will feel like a challenge but it is a prudent decision to proactively begin planning and preparing for necessary changes. Pointing to the benefits can help justify the need. Some of the benefits of application modernization include:

Improved Performance. A streamlined, efficient application can greatly improve user experience by being more responsive to input, more intuitive to use, and providing expected output more quickly. Part of this improvement can also be driven by scalability. An application that effortlessly and automatically scales to support heavy usage is by definition a better performing application.

Reduced Cost. Running on a more efficient or smaller infrastructure footprint reduces operational costs and simplifies maintenance requirements. Just as with performance, scalability helps with costs as well. For example, cloud based elastic auto scaling models allow businesses to scale their infrastructure to meet demand. The days of over-provisioning for one-time peak events can be left in the past. Finally, and perhaps most importantly, modernization can reduce cost by removing dependencies on third party vendors with licensing costs that can feel downright punitive.

Team Productivity. Engineering teams can focus time and energy on higher-value work by improving or removing software that requires time-intensive deployments, high-maintenance support, or legacy expertise.

Meet the Needs of the Business. Adapt and respond to business priorities through increased  responsiveness, quicker development, and reliable deployment of new features and functionality for users. An accelerated innovation cycle and time to market (e.g., when you spend less on maintenance you have more margin to spend on R&D) paired with automated, streamlined, modern deployment processes help development teams provide value that is directly tied to business needs and priorities. 

Future-Proofing. Benefit from aligning and integrating your application with modern, cloud-compatible technologies that enable improved security, agility, reliability, and best practices.


Categories of application modernization


CI/CD pipeline development


Continuous integration (CI) is a process where code changes are committed to a central repository and kick off an automated process to build and test the application with the new code. This automation shortens the feedback loop on new changes. Engineers can understand how their changes affect the application, and then address issues and resolve bugs more quickly and efficiently. In addition to simplifying and automating, CI also expands what is possible both at the people level and the systems level. For example, a CI process can run several end-to-end integration tests in parallel that would not be feasible for individual developers to coordinate on their own, or to run on their local machines. Adding CI processes will convert local, narrow, individualized testing practices into systemwide, standardized, orchestrated workflows.

Continuous delivery or continuous deployment (CD) comes after the CI process and continuously prepares the application to be deployed to different environments. The full CI/CD pipeline is a major component of an agile development process where changes can be deployed quickly, efficiently, and with less manual interaction. In addition to streamlining work for your development team, this automation allows for greater flexibility and responsiveness to the needs of the business and users.

Building a CI/CD pipeline is a highly customizable component of application modernization. It should be tightly aligned with requirements specific to the application as well as engineering team norms and standards. This custom workflow will include several stages with differing levels of complexity. Because this piece is highly customizable and doesn’t usually require application code changes, it will often be one of the most impactful components of application modernization and come with the lowest investment requirement.


Container adoption



While lift-and-shift rehosting is a good first step for some applications, it is not sufficient for a true modernization initiative. To truly be modernized an application must leverage cloud-native technologies by replatforming. Containerization is often the first step to replatforming and it is the process of taking everything your app needs to run – OS, libraries, dependencies – and packaging them into a container that can be deployed on any infrastructure. Since your app will have everything it needs already packaged in the container it can run on a variety of hosts which makes it very portable, versatile, scalable, and lightweight.

This approach allows for your existing application code to be deployed to multiple environments. Instead of being highly dependent on specific hardware, OS, or other expensive or hard-to-maintain requirements, your containerized application can be run on inexpensive hosts and be moved and scaled easily.


Application refactoring


Refactoring is rewriting or restructuring application code. The desired outcome is for the application to maintain the same features, but to run more efficiently with better performance and reduced operational overhead. This creates opportunities for easier maintenance and application updates through the use of modernized coding practices, along with leveraging new technologies or computational methods provided by cloud infrastructure and services.

Refactoring can also be combined with writing new code as part of breaking a monolith into microservices. This also can include rearchitecting the application where the existing monolith code needs to be restructured into logical components. These components can then be implemented and deployed independently which often requires additional coding for proper integration and functionality. This is a popular architectural choice and allows for straightforward implementation and simplified application maintenance as part of a comprehensive modernization strategy.

Refactoring typically requires more time and resources than replatforming but provides better returns by realizing additional operational efficiencies and cost optimizations. Preparing your application to begin leveraging cloud functionality like on-demand compute, resource elasticity, and massive scaling will open the door to cost savings that will recoup the required investment. Legacy applications are usually very good candidates for refactoring and rearchitecting.

Cloud native services


Cloud native simply means that everything relating to the application was built in the cloud and exists in the cloud utilizing purpose-built, managed services. Application modernization using cloud-native services provides several advantages over legacy applications such as being managed, highly scalable, resilient, and flexible.

Since all cloud native services are managed services they provide benefit by operating and maintaining the underlying infrastructure to reduce operational overhead, inefficiencies, and risk. Many of these services also take it a step further and automate common activities like monitoring, patching, and backup out of the box. 

One specific category of cloud native services is serverless computing. This is a popular approach to application modernization and offers many benefits. Serverless concepts include running custom code on demand, such as AWS Lambda, without paying for costly, unused infrastructure, storage such as EFS and S3, and databases such as AWS Aurora and AWS Athena that can scale almost infinitely. Serverless computing enables a key concept called “scale to zero”. Legacy provisioning practices require expensive infrastructure regardless of application usage whereas scale-to-zero means that your infrastructure needs (and costs!) are reduced to zero when your application is idle and then scaled back up when needed. Serverless is an increasingly attractive option for application modernization with its extreme scalability, resiliency, flexibility, and scale-to-zero capabilities that bring cost efficiency and ease of management.


The building blocks of application modernization 


Automation and orchestration

Any modernized application will leverage automation and orchestration. Automation focuses on completing specific tasks, such as running a series of unit tests, efficiently and reliably without human intervention. Orchestration coordinates and manages a set of these automations, such as a full CI/CD pipeline or container deployments, to create a cohesive, standardized, rules-based workflow.

One important outcome of application modernization is ease of application management. To achieve and optimize this goal your application should include a fully automated build and deployment pipeline that can deploy to multiple environments. This pipeline will include stages for automated testing, approvals, artifact versioning, and even business logic as needed. In addition to being critical for modernization, setting up a fully automated pipeline is also a key component in operational excellence and the ongoing management of modern applications.

When it comes to implementing this automation and orchestration, there are several categories of tools covering source code management, build, test, artifact management, deployment, and overall orchestration. You may already have some of these tools in your environment, and many of these tools can perform multiple orchestration functions. 

Source code: GitHub, GitLab, BitBucket

Dependency Management: Maven, npm, NuGet, pip

Test: JMeter, Selenium, Cypress

Deployment: Octopus, Ansible, Chef

Orchestration and Build: GitHub actions, GitLab CI

If you are already in the AWS ecosystem, and for a truly cloud-native solution, you have a suite of tools available and ready to use. Two logical places to start are AWS CodeCommit which is a git-based, source code management tool, and AWS CodeBuild which is a highly scalable build and test server that easily integrates with other build and testing tools you may already be using. After setting up source control and build automation you will be ready to continue with further orchestration. For storing build artifacts AWS CodeArtifact is a cost effective artifact storage solution and AWS CodeDeploy deploys your build artifacts to your fleet of resources. And AWS CodePipeline is the orchestration tool that will link all of these services and automations together.

API and composability

In a composable architecture APIs are leveraged to achieve a flexible approach to application development and management. APIs can be easily updated without breaking old integrations, and new API versions can be created with no downtime. Using composability your modernized application can become nimble, flexible, and responsive to changing needs, and you can leave behind concerns about your legacy application being brittle, rigid, and risky to change.

As difficult as this task may sound, Amazon provides the tools for the job. Amazon API Gateway is a simple, secure, and scalable way to front your APIs and comes with the ability to version your endpoints. Deploying these APIs using one of Amazon’s serverless offerings, such as AWS Lambda or AWS Fargate, delivers a very cost efficient solution while also making old API versions easier to maintain. In this servless model you only pay for invocations of your old API which creates an inexpensive way to support legacy processes.

Cloud infrastructure deployments

As you continue to leverage additional cloud native services, it will become critical to improve and standardize how you deploy. A key concept for this standardization is implementing infrastructure as code (IaC). Using IaC means that you interact with your infrastructure and your code in the same ways, for example by using source control, branching, and managing versions for deployment to different environments. Running code to create infrastructure on demand is a central tenet for cloud computing so as you embrace the cloud this will become more important. The idea of tearing down and spinning up entire environments at will becomes not only possible but standard practice. For example, developers should be able to provision their own test environments and deprovision them after their work is complete.

The tools used to manage and deploy IaC in AWS come with a lot of options. The two AWS native approaches are AWS CloudFormation which is a good entry point and AWS Cloud Development Kit (CDK) which is a newer, more advanced option. Using either of these tools allows you to write your infrastructure as JSON or YAML code which then enables you to deploy infrastructure multiple times to multiple environments. One improvement of AWS CDK over CloudFormation is that using the CDK allows you to write and organize infrastructure in a modern coding language like Java, Typescript, C#, Go, or Python. This brings the infrastructure even closer to your development team which empowers them to not only own how the application functions but also when, where, and how the infrastructure is operated.

Caylent’s approach to application modernization

As you can see, application modernization is a big topic. The strategies and the pitfalls are wide ranging, but the benefits are worth it. If you have big ideas for your application modernization, getting started with Caylent’s deep expertise in cloud native development is the fastest way to bring those ideas to life. We have helped our clients modernize applications using these strategies and can help you achieve the application modernization goals and requirements you need for your business. As a Premier Tier AWS consulting partner and the AWS Innovation Partner of the Year, we are here to help you achieve great outcomes for your business.

We are all-in on AWS. We have deep expertise and knowledge, and your application modernization will be delivered by AWS certified architects and software engineers. 

We are trusted and proven. We consistently achieve 9.5+ CSAT scores with our clients and we will bring this same level of excellence to your project.

We have broad industry specializations in the areas of SaaS, Healthcare, Life Sciences, Financial Services, Insurance, Education, and Transportation. 

Next Steps

Check out how Caylent can accelerate your cloud native journey. We’d love to learn more about your business and application modernization goals.

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